Cam controlled grinding machine

ABSTRACT

A grinding apparatus having a cam member with a surface corresponding to the surface of a workpiece to be ground, a cam follower mechanism for moving along the cam surface, structure for supporting the workpiece in fixed position relative to the cam member, and a grinding element movable with the cam follower mechanism along the surface of the workpiece to be ground.

United States Patent 1191 Hoglund CAM CONTROLLED GRINDING MACHINE [75] Inventor: Nils 0. Hoglund, Short Hills, NJ.

[73] Assignee: Tri-Ordinate Corporation, Berkeley Heights, NJ.

[22] Filed: July 13, 1972 [21] Appl. No.: 271,571

Related US. Application Data [60] Continuation-impart of Ser. No. 237,175, March 22, 1972, which is a division of Ser. No. 164,406, July 20, 1971, Pat. No. 3,663,188, which is a continuation-in-part of Ser. No. 147,145, May 26, 1971, abandoned.

52 us. a. 51/101 R, 51/50 PC 51 1m. (:1 B241) 17/02, B24b 17/08 58 Field of Search 51/101 R, 90,50 PC [56] References Cited UNITED STATES PATENTS 2,415,062 1/1947 Green 51/101 R 7 July 9, 1974 2,421,548 6/1947 Davies 51/101 R 2,445,971 7/1948 Rosen 51/101 R 2,487,201 11/1949 Van Buren 51/101 R X 2,592,875 4/1952 Durland 51/101 R 2,836,936 6/1958 Lovely 51/101 R X 3,435,563 4/1969 Reaser 51/101 R 3,526,060 9/1970 Hall 51/90 Primary Examiner-Donald G. Kelly Attorney, Agent, or FirmPennie & Edmonds 1 1 ABSTRACT A grinding apparatus having a cam member with a surface corresponding to the surface of a workpiece to be ground, a cam follower mechanism for moving along the cam surface, structure for supporting the workpiece in fixed position relative to the cam member, and a grinding element movable with the cam follower mechanism along the surface of the workpiece to be ground.

19 Claims, 9 Drawing Figures {mammal 91914 3322.511 SHEET 1 BF 7 Pmmsum 91914 3.822.511

SHEET 2 OF 7 FIG. 3

PATENTEUJUL 91914 3.822.511

SHEET 3 BF 7 FIG. 4

PATENTEDJUL 91914 SHEET 4 0F 7 FIG. 5

PATENIEDJUL 91914 3,822,511

SHEEY'IUFT RELATED APPLICATIONS This application is a continuation-in-part of my copending application, Ser. No. 237,175, filed Mar. 22,

1972, entitled CAM CONTROL GRINDING MA.

is a continuation-in-part application of application, Ser.

No. 147,145, filed May 26 1971, entitled CAM CON- TROL GRINDING MACHINE and now abandoned.

BACKGROUND OF THE INVENTION The cam controlled grinding machine disclosed in my earlier applications and patentis particulary suited for grinding the internal surfaces of workpieces as, for example, the intemal surface of the stator part of a Wankel-type engine. The cavity surface of the Wankel-type engine is epitrochoidal in shape; and as such produces problems in grinding which are overcome by my prior grinding machine. In particular, the grinding machine of my prior inventionpermits precise grinding and finishing of the cavity surface to tolerances theretofore not obtainable on a commercial scale. With by prior grinding machine, Wankel engines for use in automobiles can be produced economically. In addition, these engines will have their internal cavity surface ground to such precision, that unreasonable wear caused by the internally driven rotor engaging against this surface is avoided; Also, the precision grinding of the Wankel engine cavity improves engine efficiency due to the precise mating of the rotor within the cavity.

My prior grinding machine has been of some significance. in the expanding commercial production of Wankel engines. This, in turn, has been of importance in view of the fact that the Wankel engine provides a great potential for reducing pollution of the environment, as is well known to those familiar with this engine. t

The grinding machine of my prior patent is particularly constructed for grinding Wankel engines containing a single cavity. With such engines, the mass of the stator is generally evenly distributed so that it is feasible to swing the stator past the grinding wheel to effect grinding. A stationary cam follower mechanism employed in my prior machine functions to hold the stator in proper alignment relative to the grinding wheel during the grinding operation.

For some uses, it is necessary to construct Wankel engines with two separate, similarly shaped cavities. For example, with a Diesel engine, the stator part of the engine will be elongated in cross-sectional shape and enlarged at one end. Two separate cavities will be formed in this stator, one large one at the large end a smaller one at the other end. With this shape and the great mass involved in making large engines, problems arise in balancing the stator during the grinding of the two cavities. With by prior grinding machine, extremely large unbalancing forces would tend to be created even at low rotational speeds of the stator. Becauseof these possible complications in grinding large multiple cavity Wankel engines with my prior grinding machine, I have developed a machine of modified con- 2 struction which is particularly suited for grinding these types of engines.

SUMMARY OF THE INVENTION In accordance with the teachings of the present invention, the grinding machine is constructed for grinding the separate cavities of the stator part of the Wankel engine while the part is held stationary and the grinding wheel moved along the surface to be ground. In addition, the cam member used in the grinding machine of the present invention is constructed with smoother cam surfaces than formed in the cam member of my prior machine. These surfaces are less subject to wear and thus provide long life for the cam member. The machine of the present invention is further constructed so that the forces involved in holding the grinding wheel against the cavity surface of the part being ground produce no tendency to unbalance the machine. The machine of the present invention is not limited to size or shape of the workpiece being ground and is capable of taking much larger workpieces aand larger grinding cuts than can be accommodated in the grinding machine of my prior invention.

In construction, the grinding machine of the present invention generally includes an annular cam member having its external surface corresponding to the internal cavity surface to beground on the workpiece. The workpiece is mounted in fixed relation to the cam member; and a grinding wheel is supported for movement along the surface of the workpiece to be ground. A cam follower mechanism is provided for controlling feeding of the grinding wheel along the surface of the workpiece.

As with my prior grinding machine, the machine of the present invention is constructed so that the axis of rotation of the cam follower will be maintained in a plane extending perpendicular to the surface of the cam member as it passes through a predetermined point. The grinding wheel is also mounted with its axis of rotation disposed in this same plane and urged in this plane toward the surface of the workpiece to be ground. Upon rotating the cam follower at a constant speed, the follower will be fed at a constant rate along the cooperating surface of the cam member. This, in turn, will cause the grinding wheel to move relative to the surface of the workpiece at a constant speed and thus effect removal of material from the workpiece at a constant rate. Also, due to the mounting of the grinding wheel with its axis of rotation in the plane extending perpendicular to the surface being ground, wear of the grinding wheel, with the resultant decrease in diameter, will not affect the grinding operation. Even grinding wheels of different diameters can be used without affecting the grinding operation and without causing any deviation from the prescribed contour desired.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the grinding apparatus of the present invention;

FIG. 2 is a view showing the workpiece, cam member, and cam follower assembly in operative relation with each other;

FIG. 3 is a cross-sectional view of the grinding apparatus ofthe present invention taken along lines 3-3 of FIG. 2;

FIG. 4 is a cross-sectional view taken along lines 4-4 of FIG. 3;

FIG. is a cross-sectional view taken along lines 5-5 of FIG. 4;

FIG. 6 is a cross-sectional view taken along lines 66 of FIG. 4;

FIG. 7 is a side view of the grinding apparatus of the present invention showing the general overall construction including the support structure for the workpiece;

FIG. 8 is a cross-sectional view taken along lines 8-8 of FIG. 7; and

FIG. 9 is a cross-sectional view taken along lines 99 of FIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in FIG. 1 the grinding apparatus fof the present invention generally includes a support base structure 1, and a vertically movable support 2 for holding the workpiece 3 to be ground. Mounted above the workpiece is a bearing housing 4 in which a bearing plate 5 is disposed for rotation and lateral movement. A grinding mechanism generally designated at 6 is attached to the lower surface of the bearing plate for grinding the workpiece. A cam 7 is secured to the top of the bearing housing; and a cam follower mechanism generally designated at 8 is secured to the upper surface of the bearing plate. This mechanism includes a power driven cam follower wheel 9 engaging the cam surface 10 of the cam member 7 to drive the cam follower mechanism around the cam member. Through the mounting of the cam follower mechanism on the bearing plate 5, its movement around the cam 7 will produce a corresponding movement of the grinding mechanism 6 relative to the workpiece 3.

In accordance with the teachings of the present invention, the cam member 7 is constructed with an external surface 10 according to the cavity wall surface ll of a stator workpiece 3 of a Wankel-type engine. A separate cam member will be required for each cavity. The shape of the cam member is most clearly shown in FIG. 2. FIG. 2 also shows the relationship between the cam surface 10 and the cavity wall surface 11 of the workpiece 3. They correspond precisely to each other in a manner similar to a punch and die. In the present machine, the cam member 7 directly overlies the workpiece sothat the surface 10 of the cam member is coincident with the surface 11 of the cavity when viewed from above.

The cam follower wheel 9 of the cam follower mechanism engages agains the cam surface 10 at the point 12 and has its axis of rotation lying in a plane P-l extending normal to the cam surface 10 at the point of contact 12. As shown in FIGS. 3-6, the cam driving follower wheel 9 is supported on the end of a spindle 13, in turn, rotatably supported in a slide member I4. The other end of the spindle extends through the slide member and is provided with a pulley 15 around which a drive belt 16 extends. The drive belt also loops around a pulley 17 fixed to the output shaft of a drive motor 18. The drive motor is mounted on the slide 14 by means of the bracket 19. The slide itself is slidably mounted in a slide housing 20 for sliding movement in a direction parallel to the plane P-l.

The cam follower mechanism also includes guide follower means 21 having a pair of wheels 22 and 23 engaging against tracking sections 24 and 25 formed on the inner surface of the cam member 7. These wheels are mounted with their axes of rotation disposed in a plane P-2 lying perpendicular to plane P-ll. The guide follower wheels are urged against the cam follower to produce a resultant force lying in the plane P-1 and extending through the point 12.

A second slide 26 is slidably mounted on the slide 14 for linear movement in the same direction as the slide 14 but relative thereto. Attached to the bottom surface of the second slide 26 is a bracket 27. The brackket 27 supports the cam guide follower wheels 22 and 23 for rotation. The Wheels 22 and 23 are disposed in spaced vertical relationship to each other for engaging, respectively, against thee upper and lower internal tracking sections 24 and 25 of the cam member 7. These wheels are also supported, as shown in FIGS. 2, in laterally offset relation to each other at equal distances from the plane P-l.

The second slide 26 is spring biased in a direction to the right as viewed in FIG. 3 in order to urge the guide follower wheels against the inner tracking sections of the cam member. For this purpose the slide 14 is provided with a plate 28 having a threaded bore 29, as most clearly shown in FIG. 6. An adjusting nut 30 is threadedly engaged in the bore 29. A rod 31 extends slidably through the adjusting nut 30 in the plane -P-1 and in the direction of the resultant force required to maintain the axis of rotation of the cam follower wheel 9 in the plane P-l. The extending end of the rod 31 is threaded into the second slide 26. Abutment means 32, comprising a thrust bearing, is slidably mounted on the rod 31 between the second slide 26 and the adjusting nut 30. Compression spring means in the form of Belleville spring washers 33 are disposed about the rod between the abuttment means and the second slide 26 to urge the second slide in a direction to the right as viewed in FIG. 6.

With the spring connection between the two slides 14 and 26, the cam follower wheel 9 on the slide 14 is urged against the external cam surface I0 while the guide follower wheels 22 and 23 are urged in the opposite direction against the inner tracking sections 24 and 25 of the cam member. The force with which the cam follower wheel and guide follower wheel are urged against the cam can be regulated by turning the adjusting nut 30. Turning the adjusting nut to move it to the right as viewed in FIG. 3 will compress the Belleville springs and thus increase the force with which the follower wheels are urged against the respective surfaces of the cam. Turning the nut in the opposite direction will have the opposite effect.

The construction of the cam follower mechanism as described above produces the required resultant force to maintain the axis of rotation of the cam follower wheel in the plane P-l as the mechanism is moved about the cam. The guide follower wheels 22 and 23, being disposed at equal distances from the plane P-I, effectively overcome inertial forces tending to cause the cam follower mechanism to rotate and shift the point 12 out of the plane P-l. Also, by having the cam follower wheel power driven at a constant speed by means of the motor 18, the follower mechanism will be fed around the cam surface 10 at a constant speed. Thus the surface 10 of the cam member will move relative to and through the point 12 at a constant rate.

As shown in FIG. 2, the upper and lower tracking sections of the cam member are of different contour. The precise contour of each tracking section is dictated by the surface 10. Along the sides, the tracking stations are clearly shown as undercutting each other opposite the portions of the cam surface which are concave. The differences in shape between the tracking sections as shown in FIG. 2 are due to the fact that a pair of offset guide wheels are used. With a pair of wheels, they will contact different points on the tracking sections at any given point in time as they are moved along the cam member. Where the cavity wall surface of the stator of a Wankel-type engine is being ground, such surface will be one of ever changing radius of curvature. Accordingly, since the guide follower wheels 22 and 23 are offset, tracking sections 24, 25 will differ in shape over their entireperiphery. The differences in shape are small and,except for the undercut sides, is not shown in FIG. 2.

As indicated above, the cam follower mechanism is mounted on the upper surface of a bearing plate 5. This mounting is provided by a bracket support 34 fixed to the upper surface of the bearing plate 5 and supporting the slide housing20. To permit movement of the follower mechanism about the cam, the bearing plate 5 is mounted for rotation about an axis lying parallel to the in floating relation within the housing. The construction of the bearing housing can be the same as disclosed in my prior Pat. No. 3,663,188.

In accordance with the teachings of the present invention, the grinding mechanism 6 includes a grinding wheel 36 mounted with its axis of rotation disposed in the same plane P-1 as is the axis of rotation of the cam I follower 9. This relationship is clearly shown in FIG. 2

where it will also be noted that the peripheral surface of the grinding wheel engages against the internal surface 11 of the workpiece at a point coincident with the point 12. The grinding wheel is fixed to the end of a spindle 37 which is, in turn, rotatably supported on a bracket 38 fixed to the bottom surface of the bearing plate 5. The bracket 38 also mounts a drive motor 39 connected to the spindle 37 by a pulley drive generally designated by reference numeral 40.

In order to feed the grinding wheel along the plane P-1 and toward the surface of the workpiece to be ground, a stepping motor 41 is provided. This motor is mounted on the slide housing and is provided with a threaded output shaft 42. The shaft 42 is threadedly received in a threaded bore 43 in the plate 28, in turn, attached to the slide 14 carrying the cam follower.

Operation of the stepping motor 41 to rotate the shaft in a direction which tends to pull the slide 14 to the left as viewed in FIG. 1, will have the effectof moving the grinding wheel 36 to the right as viewed in FIG. 1. This is so since the cam follower wheel 9 which is fixed to the slide 14 cannot move to the left because of its engagement with the fixed cam member 7. The stepping motor is, however, mounted on the slide housing 20 and the housing 20 is supported by the floating bearing plate 5. Due to this and the fact that the bearing plate is free to float within the bearing housing 4, such plate will move to the right as viewed in FIG. 3. With the grinding wheel fixed to the lower surface of the bearing plate by means of the bracket 38, this movement will, in turn, cause the grinding wheel 36 to move to the right as viewed in FIG. 3 and into grinding engagement with the surface of the workpiece to be ground.

An important feature of the construction of the present invention resides in the manner in which the grinding wheel is urged against the surface of the workpiece to be ground. The pressure created from the grinding wheel engaging the workpiece is not in the directon of the spring loading of the cam guide follower wheels 22, 23. It is, instead, in a direction directly against the pressure created by the cam follower wheel 9 engaging the cam surface 10. Thus, there is no tendency for the cam follower mechanism to become disengaged from the cam member under the highest of loads created during grinding operations.

Another advantage of the grinding machine described above resides in the fact'tlhat the grinding wheel will effect removal of material from the workpiece at a constant rate. This is so since the grinding wheel will be fed, by the cam follower mechanism being driven around the cam member, at a constant rate of speed. This constant rate of removal of material from the workpiece and the advantages thereof are further described in my prior Pat. No. 3,663,188.

In operation of the grinding machine, the drive motors l8 and 39 for the cam follower wheel 9 of the grinding wheel 36 are adapted to be driven hydraulically. A source of hydraulic pressure generally designated by reference numeral 44 is provided at a location remote from thegrinding apparatus. The source is connected to thedrive motors by hydraulic lines 45, 46 and 47. As shown in FIG. 3, the line extends to a manifold 48 for supplying hydraulic fluid to the drive motor 39 by way of a secondary hydraulic line 45. The second hydraulic line 46 extends to a manifold 49 for supplying hydraulic fluid through a secondary line 50 to the drive motor 18 for the cam follower wheel 9.

The return line for the drive motor 39 is shown at 51 in FIGS. 5 and 6 as extending parallel to the line 45, This return line is connected at its lower end to the manifold 48 and at its upper end to themanifold 49. Secondary return line 51' connects the manifold 48 to the motor 39. The return line for the hydraulic motor 18 includes a secondary line 52, also connected to the manifold 49. Inside the manifold 49, the return lines for both the drive motor 39 and the drive motor 18 are connected to the single hydraulic line 47 which leads back to the source 44. This construction provides an efficient and compact manner of supplying hydraulic fluid to each of themotors.

As will be recognized, the hydraulic motor 39 for operating the grinding wheel, by being mounted on the bearing plate 5, will have to move relative to the support structure of the grinding machine. Such movement will be necessitated as the cam follower mechanism and grinding wheel are moved around the fixed cam member and fixed workpiece. Also, movement of the grinding wheel and its motor with respect'to the cam follower mechanism will be required during feeding of the grinding wheel into the workpiece. To accommodate this movement, the horizontal sections of the hydraulic lines 45-47 are connected to the vertical sections above the cam follower mechanism by way of swivel connections 53. These connections permit the vertical sections of the hydraulic lines to pivot about their axes. In addition to this pivot connection, the horizontal sections of the hydraulic lines are mounted for swinging movement about bearing support 54. More particularly, these lines extend through a swivel block 55 rotatably secured at the upper end of the bearing support. The swivel block, in turn, accommodates ball bushings 56 through which the hydraulic lines extend in sliding relation.

The vertical sections of the hydraulic lines 45 and 51 extending down to the drive motor 39 pass directly through the cam follower mechanism and cam memher. As shown in FIGS. 3, 6 and 7, these lines extend through the opening in the cam member inherently provided by its annular nature. The slide members 14 and 16 disposed above the cam member are also provided with openings 57, 58, respectively, aligned with the opening through the cam member. As shown, these openings are larger than the cross-sectional dimension of the lines 45 and 51 so as to provide lateral clearance for these lines. This lateral clearance is necessary since the slides must be capable of moving relative to each other and relative to the grinding wheel. The bearing plate 5, bracket support 34 and slide housing are also provided with openings through which the hydraulic lines 45 and 51 can pass. These openings however, need not provide any lateral clearance for the lines since all of this structure is fixed relative to the drive motor 39 which is attached to the bottom of the bearing plate. With the construction described above, the cam follower mechanism will move along the stationary annular cam member upon power being supplied to the drive wheel. This movement of the cam follower mechanism and the bearing plate 5 on which it is mounted will cause a similar movement of the grinding wheel 36.

As shown in FIGS. 3 and 4, the workpiece 3 is adapted to be positioned below the cam follower mechanism in cooperating relation with the grinding wheel 36. FIGS. 7, 8 and 9 show the structure for mounting the workpiece in this position. First of all, it is to be noted that the two supporting upright members 59 carry a cross member 60 which supports all of the structure of the grinding machine so far described at a location spaced above-the supporting base structure 1. The workpiece 3 is contained within a work holder 61. The holder 61 is, in turn, mounted on the vertical movable support 2 which comprises a slide 62. The slide has two hydrostatic bearings 63 that are guided on two vertical rods 64. The rods are supported inside upright members 59 by upper and lower support blocks 65 and 66.

The whole slide assembly, consisting of the workpiece holder 61, the slide 62 and the hydrostatic bearings 63, is adapted to be moved from the lower position shown in solid lines in FIGS. 7-9 to a raised position where the workpiece is aligned with the grinding wheel. For this purpose, a hydraulic cylinder 67 is disposed beneath the slide 62 with its piston rod 68 connected to the slide. Actuation of the hydraulic cylinder to cause extension of the piston rod 68 will move the slide assembly with the workpiece secureed thereon to a raised position where the grinding operation can commence. The raised position of the workpiece is shown on solid lines in FIGS. 3 and 4 and in dotted lines in FIG. 9. When in raised position, the grinding wheel will be fed toward the workpiece by the stepping motor 41 to effeet proper grinding of the workpiece as the wheel is moved along the workpiece by the cam follower mechansim. Grinding will continue until such time as automatic gauging equipment senses that the part has been ground to the proper size. At this time, automatic controls will stop the grinding operation and retract the workpiece to its lowered position where it can be removed and a new workpiece automatically loaded into the machine. After all of the cavities of the one size in the stator part have been ground, the cam member 7 will be replaced by another cam member having a shape corresponding to the other sized cavities of the stator part. Grinding of these cavities will then be commenced.

At the down position of the workpiece, the grinding wheel may be dressed by a suitable diamond wheel dressing mechansim. The dressing mechansim, not shown, may be attached to the bracket 38; and suitable automatic controls can be provided for effecting a dressing operation. After the dressing operation has been completed the new workpiece can then be raised to a grinding position and the grinding cycle repeated.

I claim: l. A grinding apparatus for grinding the surface of a workpiece comprising:

a. a cam member having a first surface with a changing radius of curvature facing in one direction and a second surface facingng in the opposite direction, said first surface corresponding to the surface to be ground on the workpiece;

b. a cam follower engaging the first surface of the cam member at a point lying in a predetermined plane extending normal to the surface at said point;

0. support means for supporting the cam follower for movement relative to the cam member along the first surface of the cam member;

(I. means for moving the cam member and cam follower relative to each other with the cam follower moving relatively along the first surface of the cam member;

e. guide follower means engaging the second surface of the cam member;

f. means for resiliently connecting the guide follower means to the cam follower for continuously holding the first surface of the cam member against the cam follower, at said point, normal to said plane as the cam member and cam follower are moved relative to each other;

g. means for fixing the workpiece relative to the cam member with the surface to be ground facing in said opposite direction;

h. grinding means for engaging along the surface of the workpiece to be ground substantially opposite the cam follower as the cam follower is moved relative to the cam member and along the first surface thereof;

i. means for supporting the grinding'means on the support means for movement, relative to the camfollower, toward the surface of the workpiece to be ground; and j. means for urging the grinding meeans into grinding engagement with the surface of the workpiece to be ground. 2. A grinding apparatus for grinding the surface of a workpiece comprising:

a. a'cam member having a first surface facing in one direction and a second surface facing in the opposite direction, said first surface corresponding to the surface to be ground on the workpiece;

.b. a cam follower engaging the first surface of the cam member;

0. support means for supporting the camfollower for movement relative to the cam member along the first surface of the cam member wherein:

l. said'support means includes first slide means for supporting the cam follower for sliding movement in a predeterminedd plane extending normal to the first surface of the cam member at the point of contact with the cam follower;

d. means for moving the cam member and cam follower relative to each other with the cam follower moving relatively along the first surface of the cam member;

e. guide follower means engaging the second surface of the cam member;

f. means for resiliently connecting the guide follower means to the cam follower for continuously holding the cam follower against the first surface of the cam member including:

l. a second slide means carried by said first slide means for. sliding movement in said predetermined plane, and

2. spring means connected between said first and second slide means for urging the slide means relative'to each other so as to urge the cam follower and guide follower means against the first and second surfaces, respectively, of the cam member;

g. means for fixing the workpiece relative to the cam member with the surface to be ground facing in said opposite direction; I

h. grinding means for engaging along the surface of the workpiece to be ground as the cam follower is moved relative to the cam member and along the first surface thereof;

i. means for supporting the grinding means on the support means for movement, relative to the cam follower, toward the surfacce of the workpiece to be ground; and

j. means for urging the grinding means into grinding engagement with the surface of the workpiece to be ground.

3. A grinding apparatus according to claim 2 wherein the means for urging the grinding means into grinding engagement with the workpiece includes:

workpiece comprising: 7

a. a cam member having a surface with a changing radius of curvature corresponding to the surface to be ground on the workpiece;

b. a cam follower engaging the surface of the cam member at a point lyingin a predetermined plane extending normal to the surface at said point; 0. support means for supporting said cam follower for movement along the surface of the cam member, said support means comprising: i 1. bearing means having an axis of rotation lying parallel to said predetermined plane, and

2. means for supporting said bearing means for rotation about said axis and for movement perpendicular to its axis of rotation;

d. means for moving said cam follower along the surface of the cam member; s

e. guide follower means for continuously holding the cam surface, at said point, normal to said plane as said cam follower is moved along the surface of said cam member;

f. means for fixing the workpiece relative to said cam member;

g. grinding means for engaging along the surface of the workpiece to be ground-as the cam follower is moved-along the surface of the cam member; and

face of a workpiece comprising:

a. an annular cam member having an external surface with a changing radius of curvature corresponding to the internal surface'to be groundon the workpiece b. a cam follower engaging the external surface of the cam member at a point lying in a predetermined plane extending normal to the external surface at said point;

e. support means for supporting said cam follower for movement along the external surface of the cam member, said support means comprising:

1. bearing means having an axis of rotation lying parallel to said predetermined plane,

2. means for supporting said bearing means for rotation about said axis and for movement in a direction perpendicular to its axis of rotation, and

3. first slide means for supporting said cam follower on said bearing means for sliding movement along said predetermined plane relative to said bearing means;

d. means for moving said cam follower along the external surface of said cam member;

e. guide follower means for continuously holding the external cam surface, at said point, normal to said plane as said cam follower is moved along the external surface of said cam member;

f. means for fixing the workpiece relative to said cam member; t

g. grinding means for engaging along the internal surface of the workpiece to be ground as the cam follower is moved along the external surface of the cam member; and

' h. feeding means for supporting the grinding means toward and away from the surface of the workpiece to be ground.

6. A grinding apparatus according to claim 5 wherein:

a. the feeding means for supporting the grinding means for movement relative to the cam follower includes:

1. means for fixedly mounting the grinding means on the bearing means, and

2. power means fixedly mounted on the bearing means and having an operating member connected to the first slide means for effecting relative movement between the first slide means and the bearing means along said predetermined plane upon actuation of said power means to thereby effect similar relative movement be tween the cam follower and grinding means.

7. A grinding apparatus according to claim 6 wherein:

a. the guide follower means engages against the inner surface of the cam member for creating a resultant force urging the cam member against the cam follower during movement of the external surface of the cam member through said point, said force lying in said predeterminedplane and extending through the point of engagement of the external surface of the cam member with the cam follower.

8. A grinding apparatus according to claim 7 further comprisng:

a. second slide means carried by said first slide means for supporting said guide follower means for sliding movement along said predetermined plane relative to said cam follower.

9. A grinding apparatus according to claim 8 further comprising: I

a. spring means connected between said first and secnd slide means for urging said slide means relative to each other so as to urge said cam follower against the external surface of the cam member and the guide follower means against the inner surface thereof.

10. A grinding apparatus according to claim 9 wherein said spring means includes:

a. a threaded bore in said first slide means;

b. a threaded adjusting nut threadedly engaged in said bore;

0. arod extending slidably through said nut and parallel to said predetermined plane in the direction of said resultant force, said rod being connected to the second slide means;

d. abutment means slidably secured to said rod between said adjusting nut and the second slide means; and

e. compression spring means positioned on said rod with one end engaging said abutment means and the other end engaging the second slide means.

11. A grinding apparatus according to claim 9 wherein:

a. the cam follower includes a wheel having its axis of rotation lying in said predetermined plane; and

b. the means for moving the cam follower along the external surface of the cam member includes a drive for rotating the cam follower wheel at a constant speed.

12. A grinding apparatus according to claim 11 wherein:

a. said grinding means includes a grinding wheel mounted for rotation about an axis lying in said predetermined plane.

13. A grinding apparatus according to claim 12 wherein:

a. the inner surface of said cam member includes two separate tracking sections disposed at different locations axially of said cam member; and

b. said guide follower means includes two cam guide follower wheels engaging individually against the separate tracking sections.

14. A grinding apparatus according to claim 13 wherein:

a. the guide follower wheels are rotatably mounted with their axes of rotation lying in a common plane extending perpendicular to said predetermined plane.

15. A grinding apparatus according to claim 14 wherein:

a. the axes of rotation of said guide follower wheels are spaced equally on opposite sides of said predetermined plane.

16. A grinding apparatus according to claim 9 wherein:

a. said bearing means includes a bearing plate disposed in a horizontal plane; and

b. the means for supporting the bearing means includes:

l. a bearing housing supporting the peripheral portion of the bearing plate from above and below.

17. A grinding apparatus according to claim 16 wherein the means for supporting the bearing means further includes:

a. fluid means for supporting said plate within said .housing for rotation and lateral movement and against vertical movement.

18. A grinding apparatus according to claim 16 wherein:

a. said cam member is fixed to the bearing housing above the bearing plate;

b. the grinding means is secured in depending relation to said bearing plate;

c. the workpiece is supported below said bearing plate to be engaged by said grinding means; and

d. said first and second slide means are disposed above said bearing plate and above the cam member by means connecting the first slide means to the bearing plate, said means including a slide housing in which said first slide means is slidably disposed, said slide housing being fixed to the upper surface of the bearing plate through the opening defined by the annular nature of the cam member.

19. A grinding apparatus according to claim 18 further including: a. hydraulic means for operating said grinding means including:

1. a hydraulic motor secured in depending relation to the bearing plate for rotating said grinding wheel,

2. a source of hydraulic power disposed remotely from the hydraulic motor, and

3. hydraulic lines connecting said source to said hydraulic motor; and

b. openings through said slide means aligned with the opening throug said cam member for permitting passage of said hydraulic lines therethrough with lateral clearance; and

c. openings through said slide housing and bearing plate aligned with the opening through said cam member for permitting passage of said hydraulic lines therethrough.

Patent No. 3,822,511 Dated July 9, 1974 Inventofls) l q nd It is certified that error appears in the above-identified patent and that, said Letters Patent are hereby corrected as shown below:

Column "1, line 63, "by" should read -my--. 1 Column 2,, line 21, "aand" should read and-f-. Column 3, li n'efl6, "Fof" should read --of--; I e

- "line-.37, "according'-' should read -'j orrespQnding"; 1 1' lijne."5l, "agains" should read -ag ai'nst- Column 4, line' l3, "thee" should read--th e'-'-; line 15, "FIGS; should read --FIG'.; 1

- 1 a line 34, "abuttment" should read .-'abutment- Column 5, .line 1, "stations" should. read -sec tions line" 34, "Pat; No. 3,663,188" should read -patent d 1 3,663,18 I g Column 6, line, 27, "Pat. No; 3,663,188" should read -patent 3,663 188' Y line 259, "of" should read and- I Column 7, line l6, "16" should read -26-;

' 1 line-64, "on" should read -in--., 7 l Claim 1, Co-lumn'8, line 29, "facingng" should read -fac':ing-:-". 7 Claim 2, Column 9, line 12, "predeterminedd" should read --predetermined- Signed and sealed this 3rd day of; Deoembefr 1974. f

(SVEAL) Arrest; v a mco'or M; GI SON JR. c. MARSHALL DANN Attesting'Oificer v a a Commissioner of Patents" a 5 (026.9,) 1 I I I 1 I I l I uscoMM-oc someoo 

1. A grinding apparatus for grinding the surface of a workpiece comprising: a. a cam member having a first surface with a changing radius of curvature facing in one direction and a second surface facingng in the opposite direction, said first surface corresponding to the surface to be ground on the workpiece; b. a cam follower engaging the first surface of the cam member at a point lying in a predetermined plane extending normal to the surface at said point; c. support means for supporting the cam follower for movement relative to the cam member along the first surface of the cam member; d. means for moving the cam member and cam follower relative to each other with the cam follower moving relatively along the first surface of the cam member; e. guide follower means engaging the second surface of the cam member; f. means for resiliently connecting the guide follower means to the cam follower for continuously holding the first surface of the cam member against the cam follower, at said point, normal to said plane as the cam member and cam follower are moved relative to each other; g. means for fixing the workpiece relative to the cam member with the surface to be ground facing in said opposite direction; h. grinding means for engaging along the surface of the workpiece to be ground substantially opposite the cam follower as the cam follower is moved relative to the cam member and along the first surface thereof; i. means for supporting the grinding means on the support means for movement, relative to the cam follower, toward the surface of the workpiece to be ground; and j. means for urging the grinding meeans into grinding engagement with the surface of the workpiece to be ground.
 2. a source of hydraulic power disposed remotely from the hydraulic motor, and
 2. A grinding apparatus for grinding the surface of a workpiece comprising: a. a cam member having a first surface facing in one direction and a second suRface facing in the opposite direction, said first surface corresponding to the surface to be ground on the workpiece; b. a cam follower engaging the first surface of the cam member; c. support means for supporting the cam follower for movement relative to the cam member along the first surface of the cam member wherein:
 2. spring means connected between said first and second slide means for urging the slide means relative to each other so as to urge the cam follower and guide follower means against the first and second surfaces, respectively, of the cam member; g. means for fixing the workpiece relative to the cam member with the surface to be ground facing in said opposite direction; h. grinding means for engaging along the surface of the workpiece to be ground as the cam follower is moved relative to the cam member and along the first surface thereof; i. means for supporting the grinding means on the support means for movement, relative to the cam follower, toward the surfacce of the workpiece to be ground; and j. means for urging the grinding means into grinding engagement with the surface of the workpiece to be ground.
 2. means for supporting said bearing means for rotation about said axis and for movement in a direction perpendicular to its axis of rotation, and
 2. power means fixedly mounted on the bearing means and having an operating member connected to the first slide means for effecting relative movement between the first slide means and the bearing means along said predetermined plane upon actuation of said power means to thereby effect similar relative movement between the cam follower and grinding means.
 2. means for supporting said bearing means for rotation about said axis and for movement perpendicular to its axis of rotation; d. means for moving said cam follower along the surface of the cam member; e. guide follower means for continuously holding the cam surface, at said point, normal to said plane as said cam follower is moved along the surface of said cam member; f. means for fixing the workpiece relative to said cam member; g. grinding means for engaging along the surface of the workpiece to be ground as the cam follower is moved along the surface of the cam member; and h. means for supporting the grinding means on said bearing means for movement in said predetermined plane relative to said cam follower and toward and away from the surface of the workpiece to be ground.
 3. first slide means for supporting said cam follower on said bearing means for sliding movement along said predetermined plane relative to said bearing means; d. means for moving said cam follower along the external surface of said cam member; e. guide follower means for continuously holding the external cam surface, at said point, normal to said plane as said cam follower is moved along the external surface of said cam member; f. means for fixing the workpiece relative to said cam member; g. grinding means for engaging along the internal surface of the workpiece to be ground as the cam follower is moved along the external surface of the cam member; and h. feeding means for supporting the grinding means on said bearing means for movement relative to said cam follower and in said predetermined plane toward and away from the surface of the workpiece to be ground.
 3. A grinding apparatus according to claim 2 wherein the means for urging the grinding means into grinding engagement with the workpiece includes: a. means for fixedly mounting the grinding means on the support means, and b. power means fixedly mounted on the support means and having an operating member connected to the first slide means for effecting relative movement between the first slide means and the support means along said predetermined plane upon actuation of the power means to thereby effect similar relative movement between the cam follower and the grinding means.
 3. hydraulic lines connecting said source to said hydraulic motor; and b. openings through said slide means aligned with the opening through said cam member for permitting passage of said hydraulic lines therethrough with lateral clearance; and c. openings through said slide housing and bearing plate aligned with the opening through said cam member for permitting passage of said hydraulic lines therethrough.
 4. A grinding apparatus for grinding a surface of a workpiece comprising: a. a cam member having a surface with a changing radius of curvature corresponding to the surface to be ground on the workpiece; b. a cam follower engaging the surface of the cam member at a point lying in a predetermined plane extending normal to the surface at said point; c. support means for supporting said cam follower for movement along the surface of the cam member, said support means comprising:
 5. A grinding apparatus for grinding an internal surface of a workpiece comprising: a. an annular cam member having an external surface with a changing radius of curvature corresponding to the internal surface to be ground on the workpiece; b. a cam follower engaging the external surface of the cam member at a point lying in a predetermined plane extending normal to the external surface at said point; c. support means for supporting said cam follower for movement along the external surface of the cam member, said support means comprising:
 6. A grinding apparatus according to claim 5 wherein: a. the feeding means for supporting the grinding means for movement relative to the cam follower includes:
 7. A grinding apparatus according to claim 6 wherein: a. the guide follower means engages against the inner surface of the cam member for creating a resultant force urging the cam member against the cam follower during movement of the external surface of the cam member through said point, said force lying in said predetermined plane and extending through the point of engagement of the external surface of the cam member with the cam follower.
 8. A grinding apparatus according to claim 7 further comprisng: a. second slide means carried by said first slide means for supporting said guide follower means for sliding movement along said predetermined plane relative to said cam follower.
 9. A grinding apparatus according to claim 8 further comprising: a. spring means connected between said first and second slide means for urging said slide means relative to each other so as to urge said cam follower against the external surface of the cam member and the guide follower means against the inner surface thereof.
 10. A grinding apparatus according to claim 9 wherein said spring means includes: a. a threaded bore in said first slide means; b. a threaded adjusting nut threadedly engaged in said bore; c. a rod extending slidably through said nut and parallel to said predetermined plane in the direction of said resultant force, said rod being connected to the second slide means; d. abutment means slidably secured to said rod between said adjusting nut and the second slide means; and e. compression spring means positioned on said rod with one end engaging said abutment means and the other end engaging the second slide means.
 11. A grinding apparatus according to claim 9 wherein: a. the cam follower includes a wheel having its axis of rotation lying in said predetermined plane; and b. the means for moving the cam follower along the external surface of the cam member includes a drive for rotating the cam follower wheel at a constant speed.
 12. A grinding apparatus according to claim 11 wherein: a. said grinding means includes a grinding wheel mounted for rotation about an axis lying in said predetermined plane.
 13. A grinding apparatus according to claim 12 wherein: a. the inner surface of said cam member includes two separate tracking sections disposed at different locations axially of said cam member; and b. said guide follower means includes two cam guide follower wheels engaging individually against the separate tracking sections.
 14. A grinding apparatus according to claim 13 wherein: a. the guide follower wheels are rotatably mounted with their axes of rotation lying in a common plane extending perpendicular to said predetermined plane.
 15. A grinding apparatus according to claim 14 wherein: a. the axes of rotation of said guide follower wheels are spaced equally on opposite sides of said predetermined plane.
 16. A grinding apparatus according to claim 9 wherein: a. said bearing means includes a bearing plate disposed in a horizontal plane; and b. the means for supporting the bearing means includes:
 17. A grinding apparatus according to claim 16 wherein the means for supporting the bearing means further includes: a. fluid means for supporting said plate within said housing for rotation and lateral movement and against vertical movement.
 18. A grinding apparatus according to claim 16 wherein: a. said cam member is fixed to the bearing housing above the bearing plate; b. the grinding means is secured in depending relation to said bearing plate; c. the workpiece is supported below said bearing plate to be engaged by said grinding means; and d. said first and second slide means are disposed above said bearing plate and above the cam member by means connecting the first slide means to the bearing plate, said means including a slide housing in which said first slide means is slidably disposed, said slide housing being fixed to the upper surface of the bearing plate through the opening defined by the annular nature of the cam member.
 19. A grinding apparatus according to claim 18 further including: a. hydraulic means for operating said grinding means including: 